Increasingly, a widespread need exists in commercial and governmental institutions for sheet processing machines, particularly mail processing machines, capable of operating at higher operation speeds with high reliabilities and short down-times. Operating sheet processing machines at or near their maximum capability is critical for optimizing output and throughput. Delays or inefficiencies in any operation in the processing of sheet articles can undesirably affect further operations downstream. Since each operation is typically synchronized to the others, delays in feeding time, as well as other operations, can be perpetuated throughout an entire sheet processing sequence or line.
Speeds and efficiencies of a sheet processing machine in high speed operations can be greatly affected by the handling of the sheet articles within the sheet processing machine. For example, demands on accuracy of sheet article positioning and alignment in the course of handling of sheet articles are greatly increased in high speed sheet or mail processing machines. False or inadequate alignment or registrations can result in misfeeds of sheet articles that can cause delays in processing.
A further example relates to processing of creased sheet articles. When processing creased sheet articles within a sheet processing machine, particular attention needs to be paid to the handling of the creased sheet articles. The crease of a sheet article can cause the sheet article to assume a non-planar position. Thus, the creased sheet article may become harder to process within a sheet processing machine. When filling an envelope within an inserter system, for example, the fold of the flap of the envelope along its hinge line often causes the envelope to assume a non-planar position, which makes handling within the inserter system more difficult. Also, the fold of the flap often causes the flap to block the mouth of the envelope. Thus, it is desirable to have the envelope assume a more planar position during processing within a sheet processing machine. Complicated mechanisms are currently used within sheet processing machines to force envelopes to assume a more planar position during processing. These mechanisms used to force envelopes to assume a more planar position during processing can slow down processing and also cause delays and inefficiencies.
Another example of where the handling of sheet articles within an inserter system can affect delays or inefficiencies relates to the filling of envelopes. The processes and apparatuses used for opening envelopes can create a bottle neck within an inserter system. Any delays or inefficiencies in such processes or apparatuses will likely affect production through the entire inserter system. Thus, any improvement in speeds or efficiencies can greatly affect production of the inserter system. For example, early steps for preparing the envelopes for insertion may be beneficial. Also, processing the envelope in a more effective manner can improve throughput of the inserter system. For instance, maximizing the amount that an envelope is held open is desirable to prevent unneeded contraction of the sides of the envelope that can result in misfeeds of insert material, while still holding the envelope opened wide enough to permit the filling of the envelope. Such an improvement could increase efficiencies in insertion of insert material into envelopes.
In light of the above, needs exist for improved handling of sheet articles within sheet processing systems, such as mail processing systems, particularly with regard to improving throughput and increasing efficiencies within a sheet processing machine.